Method for color matching of bright paint

ABSTRACT

The following steps (1) to (3) are executed by using a computer toning apparatus constituted by (A) a calorimeter, (B) micro-brilliant-feeling sample-color tags, and (C) a computer in which a plurality of paint blendings, color data and micro-brilliant-feeling data corresponding to the paint blendings, and color characteristic data and micro-brilliant-feeling characteristic data of a plurality of primary-color paints are entered and a color-matching logic works: (1) a step of measuring a reference color with which a paint color should be matched by a colorimeter and obtaining the color data of the reference color, (2) a step of comparing the reference color with the micro-brilliant-feeling sample-color tags and deciding the micro-brilliant-feeling of the reference color, and (3) a step of comparing the color data and micro-brilliant feeling of the reference color with the color data and micro-brilliant feeling data corresponding to the paint blendings previously entered in the computer, and selecting a prospective paint blending.

TECHNICAL FIELD

The present invention relates to a computer toning apparatus and atoning method of a paint having brilliant feeling using microbrilliant-feeling sample-color tags.

BACKGROUND ART

A color matching system using a computer is publicly known as describedin the specification of U.S. Pat. No. 3,601,589. The above U.S. Patentdiscloses a method in which all spectral reflectances of an unknowncolor panel are decided by a scanning spectrophotometer and sent to acomputer, and the computer mathematically processes previously storeddata showing K-value (indicating “light absorption factor”) and S-value(indicating “light scattering factor”) to perform logical colormatching.

The disclosed contents of the above U.S. Patent basically relate to aseries of computing procedures. That is, according to the computingprocedures, it is possible to compute K-value and S-value for each ofspectral wavelengths and moreover decide K- and S-values of acombination of a pair of pigments so that the values become equal to K-and S-values of an unknown color for each of the above spectralwavelengths. This is a basic color-matching algorithm used for otherspectral-light-intensity-based color matching systems.

The system according to the above U.S. Patent has the following twoproblems: the first problem is that the system is very expensive and themaintenance of the system is difficult and the second problem is thatlogical color matching is performed by using the data of an unknowncolor obtained for a known pigment. That is, a color finally obtained bymixing pigments in accordance with a color value obtained by computationmay become a color different from the above unknown color. Therefore,because the above color-matching formula is a primary mathematicalapproximation method, it is normally necessary to correct and adjust thesystem.

To improve the system, the official gazette of Japanese Patent Laid-OpenNo. 153677/1989 discloses a method and an apparatus of analyzing aselected color by a portable color meter, storing the color data showingthe hue, chroma, and lightness of the selected color, connecting thecolor data in the color meter to a computer, storing a plurality ofusable color formulas (paint blending) in the computer, storing the datashowing hues, chromas, and lightnesses of paints designated by thestored usable color formulas in the computer, finding the mostapproximate matching by comparing the data of the selected colorreceived from the color meter with the stored color data showing thestored usable color formulas, selecting a stored color formula shown bythe color data found as the most approximate matching, and therebyperforming color matching for the selected color.

Moreover, as paint colors of automobiles, the number of paint colorshaving brilliant feeling is recently increased in which aluminum powderor brilliant mica is blended from the viewpoints of diversification ofpersonal tastes and improvement of beauty. When performing colormatching to repair-paint the paint colors having brilliant feeling, thecolor-matching accuracy of the color-matching method disclosed in theofficial gazette of Japanese Patent Laid-Open No. 153677/1988 is notsufficient yet and a color-matching method for paint colors havingbrilliant feeling by a computer has not been proposed so far. Moreover,there is a problem that toning of a paint color having brilliant feelingis difficult for an immature toning person.

Furthermore, because a marketed calorimeter cannot perform measurementseparate from brilliant feeling, micro brilliant feeling e.g. graininessof aluminum) may not be frequently adjusted though a color is toned.

It is an object of the present invention to provide a computer toningmethod capable of accurately toning a paint color having brilliantfeeling and allowing an immature toning person to easily perform toning.

BRIEF SUMMARY OF THE INVENTION

The present inventor found that the above object can be achieved byusing a computer toning apparatus constituted by a calorimeter, microbrilliant-feeling sample-color tags, and a computer to which variouspaint blendings and paint-color data values are input and in which acolor-matching computation logic works and finished the presentinvention.

That is, the present invention provides a toning method of a painthaving brilliant feeling (hereafter may be referred to as a first toningmethod), characterized by executing the following steps (1) to (3) by acomputer toning apparatus constituted by (A) a calorimeter, (B) microbrilliant-feeling sample-color tags, and (C) a computer in which aplurality of paint blendings, color data and micro brilliant-feelingdata, and color characteristic data of a plurality of primary colors andmicro brilliant-feeling characteristic data are entered and acolor-matching computation logic using the paint blendings and the datavalues works. That is, the present invention comprises:

(1) a step of measuring a reference color to which a paint color shouldbe adjusted through toning by a colorimeter and obtaining the data ofthe reference color;

(2) a step of comparing the reference color with micro brilliant-feelingsample-color tags and deciding the micro brilliant feeling of thereference color; and

(3) a step of comparing the color data and micro brilliant feeling ofthe reference color with the color data and micro brilliant-feeling datacorresponding to paint blendings previously entered in a computer,indexing matching degrees between colors and micro brilliant feelings ofthe entered paint blendings, and selecting a prospective paint blending.

Moreover, the present invention provides the above toning methodcharacterized by executing (4) a step of correcting the selectedprospective paint blending by using a color-matching computation logicand obtaining a corrected blending closer to a reference color after theabove step (3).

Furthermore, the present invention provides the above toning methodcharacterized by transferring the prospective corrective paint blendingobtained in the step (3) or the corrected blending obtained in the step(4) to an electronic balance.

Furthermore, the present invention provides a toning method of a painthaving brilliant feeling (hereafter may be referred to as second toningmethod) characterized by executing the following steps (5) to (7) by acomputer toning apparatus constituted by (A) a colorimeter, (B) microbrilliant-feeling sample-color tags, and (C) a computer in which aplurality of color numbers, paint blendings correspond to the colornumbers, color data and micro brilliant-feeling data corresponding tothe paint blendings, and color characteristic data and microbrilliant-feeling data of a plurality of primary-color paints areentered and a color-matching computation logic using the paint blendingsand the data values works. That is, the present invention comprises:

(5) a step of measuring a reference color to which the color of a paintshould be adjusted by a colorimeter through toning and obtaining thedata of the reference color;

(6) a step of comparing the reference color with micro brilliant-feelingsample-color tags and deciding the micro brilliant feeling of thereference color; and

(7) a step of selecting the color data and micro brilliant-feeling dataof at least one paint blending having the color number same as thepreset color number of the reference color, comparing the color data andmicro brilliant-feeling data of the selected paint blending with thecolor data and micro brilliant feeling of the reference color, indexingthe matching degree between the color and the micro brilliant feeling ofthe selected paint blending, and selecting a prospective paint blending.

Furthermore, the present invention provides the above toning methodcharacterized by executing (8) a step of correcting the selectedprospective paint blending by a color-matching logic and obtaining acorrected blending closer to a reference color after the above step (7).

Furthermore, the present invention further provides the above toningmethod characterized by transferring the prospective paint blendingobtained in step (7) or the corrected blending obtained in step (8) toan electronic balance.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 depicts a flow sheet of the method according to the presentinvention

Best Mode for Carrying Out the Invention

A toning method of the present invention is described below in detailand is depicted by the flow sheet of FIG. 1.

A toning method of the present invention is a method for toning a painthaving brilliant feeling capable of forming a brilliant paint film byusing a colorimeter (A), micro brilliant-feeling sample-color tags, anda computer (C) in which a color-matching logic works to be describedlater.

The above paint having brilliant feeling can use any one of paintscontaining brilliant pigments having brilliant feeling and interferenceaction such as flaky aluminum powder, vapor-deposition aluminum powder,colored aluminum powder, mica-like iron oxide, mica powder,metal-oxide-covered mica powder, metal-oxide-covered silica flake, andbrilliant graphite, brilliant-material powder such as metallic powdersuch as copper powder, and coloring pigment according to necessity.

Colorimeter (A)

A colorimeter (A) is a unit for obtaining the color data of a paint filmby measuring the color of the paint film and it is possible to use anyknown calorimeter as long as it can achieve the above object.

It is preferable to use a multi-angle calorimeter capable of measuringmany angles as a colorimeter. In the case of the multi-anglecalorimeter, measurement is performed under two or more conditions inwhich two or more angle conditions, usually two to four angleconditions, that is, incident angles of the light to be measured aredifferent from each other or two or more conditions in whichright-receiving angles formed between a mirror-surface reflection axisand a light-receiving axis are different from each other. Themirror-surface reflection axis is an axis for forming a reflection anglewhen an incident angle and the reflection angle are equal to each other,that is, an axis in which the reflection angle is 45° when the incidentangle is 45°.

To change light-receiving angles, the angle condition is not restricted.In general, however, the following cases are preferable because it iseasy to correspond to determination of a color according to visualobservation: when there are two angle conditions, these two conditionsare applied to ranges of the light-receiving angle between 15° and 30°and between 75° and 110° one each; when there are three angleconditions, these conditions are applied to ranges of thelight-receiving angle between 15° and 30°, between 35° and 60°, andbetween 75° and 110° one each; and when there are four angle conditions,these conditions are applied to ranges of the light-receiving anglebetween 15° and 30°, between 35° and 60°, between 70° and 80°, andbetween 90° and 110° one each.

Each measured value (angular reference measured value) obtained bymeasuring the color of the above paint film in accordance with eachangle condition can use any value as long as the value can specify acolor by expressing or computing the lightness, chroma, and hue. Forexample, it is possible to express the lightness, chroma, and hue by anXYZ color specification system (X, Y, and Z), L*a*b* color specificationsystem (L*, a*, and b* values), Hunter's color specification system (L,a, and b values), L*C*h color specification system (L* value, C* value,and h value) specified in CIE (1994), or Munsell color specificationsystem. Particularly, indication by the L*a*b* color specificationsystem or L*C*h color specification system is generally used forindication of a color in industrial fields including the automobilerepair-painting field.

Micro-brilliant-feeling sample-color Tags (B)

Micro brilliant feeling denotes the texture of the peculiar brilliancerevealed in a paint color containing a brilliant pigment such asaluminum powder or brilliant mica powder. For example, the microbrilliant feeling corresponds to the graininess, glittering or dazzlingfeeling, or rough texture of aluminum or mica, or size of particles. Themicro-brilliant-feeling sample-color tags (B) are used to compare apurposed paint color with the micro brilliant feeling of a referencecolor to be matched, select color tags having similar micro brilliantfeeling, and decide the micro brilliant feeling of a purposed paint filmout of the color tags. For example, the tags (B) can besystematically-arranged color tags prepared by applyingbrilliant-material-contained paints obtained by changing qualities,particle diameters, and blending quantities of brilliant materials andthereby blending the materials to a substrate and drying the paints.

Specific examples of the micro-brilliant-feeling sample-color tags (B)include a booklet and a card in which paint colors of domestic andforeign automobiles are printed for each year and each automobile makerin the field of repair painting of automobiles.

Micro-brilliant-feeling data values, color numbers, or color names aredescribed in the micro-brilliant-feeling sample-color tags (B) and it isnecessary that micro-brilliant-feeling data can be extracted from thesecolor numbers or color names.

Though various types of data values are considered as themicro-brilliant-feeling data values, the present inventor et al. findthat micro-brilliant feelings are well matched when two parameters “MGR” and “MBV” well coincide with each other and describe a toning methodof a paint using these micro-brilliant-feeling parameters in thespecification of Japanese Patent Application No. 28414/2000. “MGR” is aparameter expressing the particle feeling {perception generated byirregular non-directional patterns (random patterns) caused byorientation and overlap of brilliant pigments in paint film} and “MBV”is a parameter obtained by digitizing the glittering feeling (perceptionof irregular fine brilliancy caused by light regularly reflected frombrilliant pigment in paint film).

“MGR” and “MBV” can be respectively obtained from a two-dimensionalimage formed by photographing the surface of a brilliant paint filmirradiated with light by a CCD camera.

“MGR” is computed in accordance with a two-dimensional power-spectrumintegrated value (hereafter may be abbreviated as “IPSL”) shown by thefollowing expression obtained by integrating the power of a low spatialfrequency component in accordance with a spatial frequency spectrumobtained by applying two-dimensional Fourier transform to the abovetwo-dimensional image and normalizing the integrated power by a DCcomponent.

Numerical Formula 1

Two-dimensional power-spectrum integrated value=$\frac{\int_{0}^{L}{\int_{0}^{2\pi}{{P\left( {v,\theta} \right)}{v}{\theta}}}}{P\left( {0,0} \right)}$

(In the above expression, v denotes a spatial frequency, θ denotes anangle, P denotes a power spectrum, 0 to L denote extractedlow-spatial-frequency areas, and L denotes the upper limit of anextracted frequency.)

It is also possible to evaluate “particle feeling” in accordance withthe value of MGR computed by the following linear expression inaccordance with the above two-dimensional power-spectrum integratedvalue (IPSL).

When the value of IPSL is 0.32 or more, the following expression iseffectuated.

MGR=[(IPSL×1000)−285]/2

When the value of IPSL ranges between 0.15 and 0.32 (both excluded), thefollowing expression is effectuated.

MGR=[IPSL×(35/0.17)−(525/17)]/2

When the value of IPSL is 0.15 or less, the following expression iseffectuated.

MGR=0

Each of the above values of MGR is a value set to 0 when a brilliantmaterial does not have particle feeling or a value set to approx. 100when the brilliant material has highest particle feeling. Thus, amaterial having higher “particle feeling” shows a larger value.

“MBV” is a value computed in accordance with the data obtained byanalyzing a two-dimensional image formed by photographing it by a CCDcamera by an image analyzer, which is obtained as described below.

That is, a two-dimensional image is divided into a lot of blocks,brightnesses of all the blocks are totalized to obtain a totalized valueand an average brightness x is obtained by dividing the totalized valueby all blocks to set a threshold value α to a value equal to or higherthan the average brightness x. It is generally proper that the thresholdvalue a is the sum of average brightnesses x and y (y is a value rangingbetween 24 and 40, preferably ranging between 28 and 36, more preferablyequal to 32).

Then, the threshold value a is subtracted from each of the brightnessesof the blocks and positive subtracted values are totalized to obtain thetotal volume V that is the sum of the subtracted values. Moreover, thetotal area S is obtained which is the total number of blocks having abrightness equal to or larger than the threshold value α (total numberof blocks having brightness equal to or higher than the above thresholdvalue α obtained by converting them into binary values in accordancewith the threshold value α). The average height PHavα of brightnesspeaks is assumed as a value obtained by multiplying the value obtainedby dividing the total volume V by the total area S by 3, that is, avalue obtained from the following expression because it is consideredthat a brightness peak can be approximated to a cone or pyramid.

PHavα=3V/S

Moreover, a threshold value β is set which ranges between the aboveaverage brightness x and the above threshold value α (both included). Itis proper that the threshold value β is equal to or less than thethreshold value α and generally the sum of average brightnesses x and z(z is a value ranging between 16 and 32, preferably ranging between 20and 28, more preferably equal to 4).

Then, the threshold value β is subtracted from the brightness of each ofthe above blocks and positive subtracted values are totalized to obtainthe total volume W which is the sum of the subtracted values. Moreover,the total area A is obtained which is the total number of blocks havingbrightness equal to or higher than the threshold value β (total numberof block having brightness equal to or higher than the threshold value βobtained by converting them into binary values in accordance with thethreshold value β). It is possible to assume the average height Phav βof brightness peaks at the threshold value β as a value obtained bymultiplying the value obtained by dividing the total volume W by thetotal area A by 3, that is, a value obtained from the followingexpression because it is considered that a brightness peak can beapproximated to a cone or pyramid.

Phavβ=3W/A

Moreover, it is possible to obtain the average particle area of opticalparticles from the total area A at the threshold value β and the numberof optical particles C showing the brightness equal to or higher thanthe threshold value β. In the present invention, an “optical particle”denotes an “independent continuum having a brightness equal to or higherthan a threshold value on a two-dimensional image”. The shape of theabove optical particle is assumed as a circle and the diameter D of acircle having an area equal to the average particle area is obtainedfrom the following expression.

Numerical Formula 2

D={square root over ((4A/πC))}

Then, the peak skirt of average PSav of brightness peaks is obtainedfrom the following expression in accordance with the above phavβ and D.

PSav=D/PHavβ

It is possible to approximately compute a brightness value BV by thefollowing expression in accordance with the brightness-peak averageheight Phavα and brightness-peak skirt of average PSav obtained asdescribed above.

BV=Phavα+a·PSav

(In the above expression, “a” is equal to 300 when Phavα is less than 25but “a” is equal to 1,050 when PHavα exceeds 45 and is equal to a valueshown by the following expression when PHavα ranges between 25 and 45.)

a=300+37.5×(PHavα−25)

The value of MBV can be obtained by computing it by the following linearexpression in accordance with the above brightness value BV.

MBV=(BV−50)/2

The value of M BV is set to 0 for no glittering feeling and set toapprox. 100 for highest-glittering feeling and increases for higher“glittering feeling”.

Computer (C) in which Color-matching-computation Logic Works

A plurality of paint blendings, color data and micro-brilliant-feelingdata corresponding to the paint blendings, color characteristic data andmicro-brilliant-feeling characteristic data of a plurality ofprimary-color paints, and according to necessity, a plurality of colornumbers and a plurality of paint blendings corresponding to the colornumbers are entered in the computer (C) in which color-matchingcomputation logics using the paint blendings and the data work.Moreover, it is allowed to enter micro-brilliant-feeling data values ofcolor numbers or color names in the computer (C) according to necessityso that micro-brilliant-feeling data corresponding to a color number orcolor name can be fetched.

It is possible that the color data corresponding to each paint blendingentered in the computer is the colorimetric data of a paint filmobtained from each paint measured by a multi-angle colorimeter.

The color characteristic data values of primary-color paints entered inthe computer can be K-value (light absorption coefficient) and S-value(light scattering coefficient) of primary-color paints. The aboveK-value and S-value can be obtained by digitizing the colorimetric dataof a primary-color paint and a diluted color of the primary-color paint.

The above color numbers entered in the computer according to necessityare usually color code numbers designated for each painted-productmanufacturing maker and paint blendings for repair painting are enteredin accordance with the color numbers. In the case of the paintblendings, one paint blending can correspond to one color number.However, actual blendings can be included and it is allowed to enter aplurality of paint blendings. Moreover, the colorimetric data of formedpaint films measured by a multi-angle colorimeter are previously enteredin the computer.

A computer toning method of the present invention includes two modessuch as a first toning method which does not have a step of selecting apaint blending out of the same color numbers by using a color number anda second toning method which has a step of selecting a paint blendingout of the same color numbers by using a color number.

First, the first toning method is described in accordance with steps inorder.

Step (1):

Step (1) is a step of measuring the paint film of a reference color withwhich the color of a paint should be matched through toning by the abovecalorimeter (A) and obtaining the color data of the reference color.

It is preferable to obtain color data under the above angle conditionsby measuring the reference color which is the color of a paint film withwhich a paint color should be matched by the multi-angle calorimeter.When forming a repair paint film in repair painting such as automobilerepair paining, it is necessary that the difference between the color ofthe paint film of a repair-painting portion and the color of a paintfilm nearby the repair-painting portion is not easily visuallyrecognized. Therefore, it is normally suitable that the above referencecolor is the color of the paint film nearby the repair-painting portion.

Step (2)

Step (2) is a step of comparing the above reference color with the abovemicro-brilliant-feeling sample-color tags (B) and deciding themicro-brilliant-feeling data of the reference color. Usually, a colortag probably nearest to the micro-brilliant feeling of the referencecolor is selected out of the micro-brilliant sample-color tags (B) todecide the micro-brilliant-feeling data in accordance with the selectedcolor tag. It is also allowed to record micro-brilliant-feeling data andthe bending ratio of brilliant materials in each color tag or it isallowed to separately obtain micro-brilliant-feeling data and theblending ratio of brilliant materials from the color number or colorname of the paint color on each color tag.

Step (3)

In step (3), a prospective paint blending is selected by comparing thecolor data of the reference color obtained in the above step (1) and themicro-brilliant feeling of the reference color obtained in the abovestep (2) with the color data and micro-brilliant-feeling datacorresponding to paint blendings previously entered in a computer andindexing the matching degree between the color and the micro-brilliantfeeling of the entered paint blending. It is possible to properly selecta prospective paint blending which may be the most rational byconsidering the matching degree of the color and micro-brilliant feelingwith a reference color and the blending data. The above selection methodis not restricted. It is preferable to select a prospective paintblending out of blendings in which the matching degree of the colordifference and micro-brilliant feeling with a reference color is kept ina certain range.

Though the first toning method uses the above steps (1), (2), and (3) asindispensable steps, it is also allowed to execute the following step(4) after step (3) in order to make a color further approach to areference color.

Step (4)

Step (4) is a step of obtaining a corrected blending made to furtherapproach to a reference color by using a computer in which a pluralityof paint blendings, color data and micro-brilliant-feeling datacorresponding to each of the paint blendings, and color characteristicdata and micro-brilliant-feeling characteristic data of a plurality ofprimary-color paints are entered and thereby correcting the prospectivepaint blending selected in step (3) by a color-matching-computationlogic using the above paint blendings and data.

It is also allowed that the first toning method further includes a stepof transferring the prospective paint blending obtained in the abovestep (3) or the corrected blending obtained in step (4) to an electronicbalance.

Then, the second toning method is described below.

In the case of the second toning method, the following steps (5) to (7)are executed by further using a plurality of entered color numbers andpaint blendings corresponding to the color numbers as the data enteredin the computer used for the above first toning method.

Step (5)

Step (5) is a step same as step (1) for the first toning method.

Step (6)

Step (6) is a step same as step (2) for the first toning method.

Step (7)

In step (7), a prospective paint blending is selected by selecting thecolor data and micro-brilliant-feeling data of at least one paintblending having a color number same as the color number of a referencecolor out of color numbers previously entered in a computer, comparingthe color data and micro-brilliant-feeling data of the selected paintblending with the color data and micro-brilliant feeling of thereference color, and indexing the matching degree of the color andmicro-brilliant feeling of the selected paint blending. It is possibleto properly select a prospective paint blending which may be the mostrational by considering the matching degree of a reference color andmicro-brilliant feeling with a reference color and blending data.

Though the second toning method uses the above steps (5), (6), and (7)as indispensable steps, it is allowed to execute the following step (8)after step (7) in order to make a color further approach to a referencecolor.

Step (8)

Step (8) is a step same as step (4) for the first toning method and astep of correcting the prospective paint blending selected in step (7)and obtaining a corrected blending made to further approach to areference color.

It is allowed that the second toning method further includes a step oftransferring the prospective paint blending obtained in the above step(7) or the corrected blending obtained in step (8) to an electronicbalance.

In the case of the above first and second toning methods, it is possibleto transfer a blending to an electronic balance through a telephone lineor an optical cable. It is possible to blend toning paints in accordancewith the transferred blending by using an electronic balance. Bypreparing a toned-paint plate coated with the toning paint, it ispossible to determine whether the paint is acceptable. If it is notacceptable, it is possible to obtain a corrected blending again byoperating a color-matching-computation logic in accordance with thebending of the toning paint and the color data andmicro-brilliant-feeling data of the toned-paint plate.

EMBODIMENT

The present invention is further specifically described below byreferring to embodiments. However, the present invention is notrestricted to the embodiments.

Apparatus Used and Measuring Method

In the case of the following embodiments, a reference color with whichthe color of a paint should be matched through toning is measured by amulti-angle colorimeter “Van-VanFA Sensor” made by KANSAI PAINT CO.,LTD. and a computer in which color characteristic data andmicro-brilliant-feeling characteristic data of a plurality of primarycolor paints are entered and a color-matching-computation logic usingblendings of the paints and the data values works uses the computercolor-matching system “Van-VanFA Station” made by KANSAI PAINT CO., LTD.The above “Van-VanFA Sensor” can obtain a color-measured value bymeasuring data under three-angle conditions in which angles formedbetween a mirror-surface reflection axis and a light-receiving axis are25°, 45°, and 75°.

Micro-brilliant-feeling sample-color tags use the “Auto Color” made byKANSAI PAINT CO., LTD. The “Auto Color” is a booklet in which paintcolors of domestic and foreign automobiles are printed for each year andeach automobile maker to compare micro-brilliant feelings between areference color and a same-color-based paint color printed in the “AutoColor” and select a paint color closest to the reference color. Themicro-brilliant-feeling measured value of the selected paint color isstored in the database of the “Van-VanFA Station”.

Embodiment

Reference colors of the paint film surface of automobiles include threecolors such as high-lightness silver metallic (silver M1),middle-lightness green metallic pearl (green MP), and low-lightness bluepearl (blue P).

Color measured values of the above three reference colors under threeangle conditions are shown below.

TABLE 1 Light-receiving Color Angle L* a* b* Silver M1 250 99.96 −1.48−0.65 45° 65.34 −0.96 −2.17 75° 42.02 −0.78 −2.38 Green MP 25° 52.28−48.18 −10.80 45° 30.39 −32.89 −11.31 75° 15.97 −22.03 −10.87 Blue P 25°15.23 −1.57 −9.57 45° 3.21 0.32 −3.68 75° 1.10 0.58 −1.08

Moreover, the following are micro-brilliant-feeling data values (MGR andMBV) of most approximate paint colors selected out of Auto Color. InTable 2, MGR is a parameter obtained by digitizing particle feeling andMBV is a parameter obtained by digitizing glittering feeling.

TABLE 2 Color MGR MBV Approximate color of silver M1 62.89 47.38Approximate color of green MP 56.50 40.50 Approximate color of blue P59.82 40.20

The following are quantities of primary-color paints (paint blendings)computed by the computer color-matching system in accordance withmicro-brilliant-feeling data values of most-approximate paint colorsselected out of measured values under three angle conditions of theabove three reference colors and Auto Color.

Type of primary-color paint Weight ratio Silver M1 Silver A (Metallicprimary color A) 41.1 Silver B (Metallic primary color B) 35.3 Black A(Black primary color A) 0.9 Blue A (Blue primary color A) 0.4 AssistantA (Aluminum orientation regulator A) 18.8 Assistant B (Aluminumorientation regulator B) 3.5 Green MP Blue A (Blue primary color A) 42.0Green A (Green primary color A) 24.0 Silver C (Metallic primary color C)15.5 Blue B (Blue primary color B) 5.0 Pearl A (Pearl primary color A)2.1 Maroon A (Reddish-brown primary color A) 1.3 Assistant A (Aluminumorientation regulator A) 8.4 Assistant B (Aluminum orientation regulatorB) 1.7 Blue P Black B (Black primary color B) 39.2 Blue C (Blue primarycolor C) 22.3 Blue D (Blue primary color D) 19.1 Pearl B (Pearl primarycolor B) 10.5 Pearl C (Pearl primary color C) 8.9

Toned-paint plates are prepared in accordance with the above paintblendings. The following able shows measured values of reference colorsand colors of the above toned-paint plates in the L* a* b* color systemwhen performing three-angle-condition measurement by the abovemulti-angle calorimeter.

TABLE 3 Light-receiving Color Angle ΔL* Δa* Δb* ΔE* Silver M1 25° 3.860.08 1.03 4.00 45° 1.78 0.09 0.96 2.02 75° 0.60 −0.03 1.23 1.37 Green MP25° 2.01 0.48 −2.77 3.46 45° 1.40 0.77 −2.23 2.75 75° 0.68 1.08 −1.511.98 Blue P 25° 3.56 −0.36 −1.16 3.77 45° 1.90 −0.25 −1.94 2.73 75° 0.68−0.06 −0.59 0.90

The micro-brilliant feelings of the toned-paint plates and referencecolors are well matched each other. However, color differences betweenmeasured values of paint colors of the toned-paint plates and measuredvalues of reference colors are large and moreover, differences aredetected in visual determination. Therefore, quantities of primary-colorpaints (additional designated quantities) required to correct colors ofpaints to be toned in accordance with color measured values at variousangles on the toned-paint plates are computed by the computercolor-matching system. Moreover, the following are the then additionaldesignated quantities to 100 parts by weight of the above toned paints.

Type of primary-color paint Part by weight Silver M1 Black A (Blackprimary color A) 3.9 Assistant A (Aluminum orientation regulator A) 0.9Assistant B (Aluminum orientation regulator B) 0.2 Green MP Green A(Green primary color A) 7.5 Assistant A (Aluminum orientation regulatorA) 0.5 Assistant B (Aluminum orientation regulator B) 0.9 Yellow A(Yellow primary color A) 1.3 Blue P Black B (Black primary color B) 17.2Blue C (Blue primary color C) 7.5

The following Table 4 shows values of ΔL*, Δa*, Δb*, and ΔE* fromreference colors when measuring toned-paint plates obtained by paintingthe plates with paints corrected by the above additional designatedquantities by a multi-angle colorimeter at various angle conditions.

TABLE 4 Light-receiving Color angle ΔL* Δa* Δb* ΔE* Silver M1 25° 0.92−0.01 −0.12 0.93 45° 0.29 −0.01 −0.07 0.30 75° −0.30 −0.08 −0.16 0.34Green MP 25° −0.07 0.61 0.54 0.82 45° −0.15 0.07 0.42 0.45 75° −0.04−0.26 0.29 0.39 Blue P 25° −1.36 0.31 0.72 1.57 45° −0.57 0.12 0.87 1.0575° −0.13 −0.01 0.25 0.29

Because color differences between measured values of paints of thesecorrected toned-paint plates and reference colors are small and resultsof color determination and micro-brilliant feeling determination throughvisual observation are acceptable. Therefore, repair painting is appliedto an automobile by using corrected toning paints to visually performequal color determination for repair painted portions of the automobileand paint-film surfaces nearby the portions and resultantly, preferablecolor matching is obtained.

The following Table 5 shows results of confirming micro-brilliantfeeling data values of micro-brilliant-feeling sample-color tags andcorrected-paint plates. Micro-brilliant-feeling data values ofreferences colors and corrected toned-paint plates are measured by amicro-brilliant-feeling measuring instrument for laboratory use made byMINOLTA CO., LTD. to process electronic images by a computer.

TABLE 5 Color MGR MBV Silver M1 Reference color 60.20 44.55Micro-brilliant-feeling 62.89 47.38 sample-color tag Correctedtoned-paint 62.34 46.88 Plate Green MP Reference color 58.00 42.63Micro-brilliant-feeling 56.50 40.50 sample-color tag Correctedtoned-paint 56.39 40.36 Plate Blue P Reference color 59.10 38.97Micro-brilliant-feeling 59.82 40.20 sample-color tag Correctedtoned-paint 58.57 39.92 Plate

As clarified by values of micro-brilliant-feeling parameters MGR and MBVshown in the above Table 5, differences between values of MGR and MBV inreference colors, micro-brilliant-feeling sample-color tags, andcorrected toned-paint plates are kept within ±3 for all paint colors (ingeneral, a person recognizes the difference between values ofmicro-brilliant-feeling parameters MGR and MBV when the differenceexceeds 3) and micro-brilliant feelings are also numerically matched.

A computer paint-toning method of the present invention allows animmature toning person to tone colors having brilliant feeling at a highaccuracy.

What is claimed is:
 1. A toning method of a paint having brilliantfeeling characterized by executing the following steps (1) to (3) by acomputer toning apparatus constituted by (A) a colorimeter, (B)micro-brilliant-feeling sample-color tags, and (C) a computer in which aplurality of paint blendings, color data and micro-brilliant-feelingdata corresponding to the paint blendings, and color characteristic dataand micro-brilliant-feeling data of a plurality of primary-color paintsare entered and a color-matching-computation logic using said paintblendings and data values works: (1) a step of measuring a referencecolor with which the color of a paint should be matched through toningby a colorimeter and obtaining color data of the reference color; (2) astep of comparing said reference color with micro-brilliant-feelingsample-color tags and deciding the micro-brilliant feeling of saidreference color; and (3) a step of comparing the color data andmicro-brilliant feeling of said reference color with the color data andmicro-brilliant-feeling data corresponding to paint blendings previouslyentered in a computer, indexing matching degrees between colors andmicro-brilliant feelings of said entered paint blendings, and selectinga prospective paint blending.
 2. The toning method according to claim 1,further characterized by executing (4) a step of correcting a selectedprospective paint blending by a color-matching logic and obtaining acorrected blending closer to a reference color after said step (3). 3.The toning method according to claim 1, characterized by transferringsaid prospective paint blending obtained in step (3) or said correctedblending obtained in step (4) to an electronic balance.
 4. A toningmethod of a paint having brilliant feeling characterized by executingthe following steps (5) to (7) by a computer toning apparatusconstituted by (A) a calorimeter, (B) micro-brilliant-feelingsample-color tags, and (C) a computer in which a plurality of colornumbers, paint blendings corresponding to said color numbers, color dataand micro-brilliant-feeling data corresponding to said paint blendings,and color characteristic data and micro-brilliant-feeling characteristicdata of a plurality of primary-color paints are entered and acolor-matching logic using said paint blendings and said data works: (5)a step of measuring a reference color with which a paint color should bematched through toning by a colorimeter and obtaining the color data ofsaid reference color; (6) a step of comparing said reference color withmicro-brilliant-feeling sample-color tags and deciding themicro-brilliant feeling said reference color; and (7) a step ofselecting the color data and micro-brilliant-feeling data of at leastone paint blending having a color number same as the preset color numberof said reference color, comparing the color data andmicro-brilliant-feeling data of said selected paint blending with thecolor data and micro-brilliant-feeling of said reference color, indexingthe matching degree between the color and micro-brilliant feeling ofsaid selected paint pant blending, and selecting a prospective paintblending.
 5. The toning method according to claim 4, characterized byfurther executing (8) a step of correcting said selected prospectivepaint blending by a color-matching logic and obtaining a correctedblending closer to said reference color after said step (7).
 6. Thetoning method according to claim 4, characterized by furthertransferring said prospective paint blending obtained in step (7) orsaid corrected blending obtained in step (8) to an electronic balance.7. The toning method according to claim 2, characterized by furthertransferring said prospective paint blending obtained in step (3) orsaid corrected blending obtained in step (4) to an electronic balance.8. The toning method according to claim 5, characterized by furthertransferring said prospective paint blending obtained in step (7) orsaid corrected blending obtained in step (8) to an electronic balance.